Systems and Methods for Wrapping a Pulp Bale

ABSTRACT

A system for pulp bale wrapping includes at least one press plate operable to press a wrapper into a pulp bale. A method for wrapping pulp bale includes disposing the pulp bale between an upper wrapper and a lower wrapper, wrapping the pulp bale in the upper wrapper and the lower wrapper, and maintaining at least one of the upper wrapper and the lower wrapper in a wrapped position by crushing the at least one wrapper into the wrapped pulp bale.

CROSS REFERENCE TO RELATED APPLICATIONS

This Application claims the benefit of priority to U.S. Provisional Application Ser. No. 61/048,650, entitled “System and Method for Wrapping a Pulp Bale”, filed on Apr. 29, 2008, and which is incorporated herein by reference for all purposes.

BACKGROUND

Pulp producers typically prepare large bales of pulp, wrap the bales of pulp, and hold the wrapping in place using metal straps. Such metal straps are problematic as they must be cut and disposed of before the bale of pulp is introduced into the paper making process. Cutting the metal straps and disposing of the waste costs time and money.

Paper straps have been considered for use as a replacement for the current metal straps. Unfortunately, paper straps have not proven strong enough to withstand contact with the forks on equipment handling the wrapped bales. In particular, paper straps traversing the bale perpendicular to the forks are prone to breakage. Such breaking leaves strap portions which must be discarded.

Hence, there exists a need in the art for advanced systems and methods for wrapping pulp bales.

SUMMARY

Embodiments of the present invention provide for wrapping a pulp bale using one or more paper straps in a manner that avoids interference of handling equipment forks with the paper straps. Wrappers are inserted into opposite sides of the pulp bale to mechanically affix the wrapper to the pulp bale. Insertion of the wrappers may involve crushing the wrappers into the pulp bale using insertion apparatus of one or more shapes. Insertion apparatus may be active or inactive components. The pulp bale is rotated ninety degrees and one or more paper straps are strapped around the pulp bale. Forks of handling equipment may then be extended under the wrapped pulp bale in a direction substantially parallel to the paper straps. The wrapped pulp bale, including wrappers and paper straps, can then be placed in a pulp making vat.

An embodiment of a method for wrapping pulp bale includes disposing the pulp bale between an upper wrapper and a lower wrapper, wrapping the pulp bale in the upper wrapper and the lower wrapper, and maintaining at least one of the upper wrapper and the lower wrapper in a wrapped position by crushing the at least one wrapper into the wrapped pulp bale. The method may further include binding the wrapped pulp bale with at least one paper strap. Binding the wrapped pulp bale may include orienting the at least one paper strap in a direction substantially parallel to forks of handling equipment. Binding the wrapped pulp bale may include positioning the paper straps at a distance from each other that is different from a distance between the forks of the handling equipment. The at least one paper strap may be oriented in a single direction.

In an embodiment of a method, crushing the at least one wrapper into the wrapped pulp bale may include applying press plates to opposing sides of the pulp bale. Crushing the at least one wrapper into the wrapped pulp bale may include lifting a portion of the pulp bale to allow for insertion of the at least one wrapper into the pulp bale. Crushing the at least one wrapper into the pulp bale may further include placing a pressure element on top of the pulp bale to prevent flexing of the pulp bale during crushing of the pulp bale. Applying press plates to opposing sides of the pulp bale may include pressing one or more insertion apparatus into the upper wrapper and the lower wrapper. The one or more insertion apparatus may include one or more active components. The method may further include rotating the pulp bale to orient the at least one paper strap in the single direction.

A system for pulp bale wrapping includes at least one press plate operable to press a wrapper into a pulp bale. The at least one press plate may comprise a pair of press plates operable to be applied to opposing sides of the pulp bale to crush the wrapper into the pulp bale. The at least one press plate may include at least one insertion apparatus configured to crush the wrapper into the pulp bale. The system may further include at least one paper strap binding the wrapper around the pulp bale in a single direction. The single direction may be substantially parallel to forks on handling equipment. The at least one paper strap may include two paper straps positioned at a distance from each other that is different from the distance between the forks.

In an embodiment of a system the at least one press plate may include multiple insertion apparatus, wherein each of the insertion apparatus has a shape. At least two of the insertion apparatus may have a different shape. One or more of the insertion apparatus may be active components. The system may further include a lifting mechanism operable to lift at least a portion of the pulp bale while pressing of the wrapper into the pulp bale. The system may further include multiple wrappers that include a lower wrapper disposed beneath the pulp bale and an upper wrapper disposed on top of the pulp bale.

DESCRIPTION OF DRAWINGS

FIG. 1 is a flow diagram depicting a process for pulp bale wrapping in accordance with various embodiments of the present invention; and

FIGS. 2 a-2 f depict an exemplary pulp bale at different stages of the processing described in relation to FIG. 1.

FIGS. 3 a-3 f depict example shapes of insertion elements that can protrude from compression plates.

FIGS. 4 a-4 b depict example compression plates with elongate insertion elements that may be used in during insertion or retraction of the insertion elements.

FIG. 5 illustrates another embodiment of an insertion element in which active component eject from the insertion element.

DESCRIPTION

Embodiments of the present invention provide for wrapping a pulp bale using one or more paper straps in a manner interference of handling equipment forks with the paper straps. Wrappers are inserted into opposite sides of the pulp bale to mechanically affix the wrapper to the pulp bale. Insertion of the wrappers may involve crushing the wrappers into the pulp bale using insertion apparatus of one or more shapes. Insertion apparatus may be active or inactive components. The pulp bale is rotated ninety degrees and one or more paper straps are strapped around the pulp bale. Forks of handling equipment may then be extended under the wrapped pulp bale in a direction substantially parallel to the paper straps. The wrapped pulp bale, including wrappers and paper straps, can then be placed in a pulp making vat.

Turning to FIG. 1, a flow diagram 100 depicts a process for pulp bale wrapping in accordance with various embodiments of the present invention. Following flow diagram 100, a pulp bale is received (block 100). A representation of a pulp bale 200 is depicted in FIG. 2 a. A typical pulp bale 200 consists of a large number of sheets 202 of pulp stacked one atop another creating a rectangular brick of pulp. When received, the sides of the pulp bale 200 appear as a stack of sheets while the top and the bottom appear as a solid sheet of pulp (i.e., the top sheet and the bottom sheet). A lower wrapper is placed under the pulp bale and an upper wrapper is placed on top of the pulp bale (blocks 110, 115). Both the upper and lower wrappers may be formed as a sheet of pulp cut of a size that allows it to be folded over and cover at least a portions of the sides of the pulp bale.

A representation of an upper wrapper 204 and lower wrapper 206 disposed in relation to pulp bale 200 is depicted in FIG. 2 b. The upper wrapper 204 and the lower wrapper 206 are folded to cover two opposing sides (block 120). In some cases, the upper wrapper and lower wrapper overlap along the sides. FIG. 2 c shows the result of folding 208 upper wrapper 204 and lower wrapper 206 over the opposing sides of pulp bale 200. Folding 208 may be facilitated with use of a mechanical apparatus. Folding 208 of the upper wrapper 204 and the lower wrapper 206 is not limited to any particular order; that is, the upper wrapper 204 may be folded first, followed by folding of the lower wrapper 206, or vice versa.

The upper wrapper 204 and the lower wrapper 206 are then mechanically crushed into and/or between the sheets of pulp in the pulp bale (block 125). This process is depicted in FIG. 2 d where two opposing press plates 210, 212 act on the bale 200, upper wrapper 204 and lower wrapper 206. Each of press plates 210, 212 include one or more insertion apparatus 214 that press/crush upper wrapper 204 and lower wrapper 206 into/between sheets 202 of pulp in pulp bale 200. The one or more insertion apparatus 214 can be protrusions from the press plates 210, 212. There can be any number of insertion apparatus 214, and the insertion apparatus 214 can be located at a number of different places on the press plates 210, 212. In some cases, insertion apparatus 214 are positioned so that they insert both wrappers 204, 206 into the pulp bale 200 when compressed.

The shape(s) of insertion apparatus 214 is not limited. In FIG. 2 d, the insertion apparatus 214 are substantially “V” shaped, but this is not required. For example, the insertion apparatus 214 can take on multiple different shapes, including, but not limited to, concave, convex, circular, rectangular, “M” shaped, “U” shaped, “W” shaped, and so on. Multiple different shapes can be used simultaneously. FIGS. 3 a-3 f illustrate numerous exemplary shapes of insertion apparatus 214 than can be formed on the plates 210, 212. The shape may be selected depending on the crushing process that is used.

The crushing or compressing process (block 125) generally involves the plates 210, 212 pressing into the bale 200, followed by a retraction or pulling away from the pulp bale 200. The crushing process (block 125) can be carried out in numerous different ways to more or less secure the wrappers 204 and 206 within the pulp bale 200. In either of the insertion or retraction steps, the plates 210, 212 can be moved forward and backward, laterally from side to side, and/or vertically up and down. For example, the plates 210, 212 may lift or drop when pulling away from the pulp bale 200.

To illustrate, FIGS. 4 a and 4 b depict plates that have elongated insertion elements 402, 404 that may be used. For example, after insertion, the insertion elements 402, 404 may be lifted by one of the plates while being dropped by the opposing plate to force the wrapper on one side of the bale to be crushed up into the bale, while forcing the wrapper on the other side of the bale to be crushed down into the bale. In such a scenario, the lifting and dropping of the opposing plates can occur while the insertion elements 402, 404 are being retracted from the bale 200. As such, lifting and dropping of the insertion elements 402, 404 can occur in conjunction with the insertion and/or the retraction of the insertion elements 402, 404.

FIG. 5 illustrates another embodiment of an insertion element 500 in which one or more active components 502 can eject 504 from the insertion element 500. There may be any number of active components 502, depending on the particular implementation. The active components 502 can eject after the insertion element 500 has been inserted into the bale 200 to thereby further force the wrapper(s) into the pulp sheets in the bale 200. Ejection of the active components 502 may be trigger by spring loading or otherwise. Ejection of the active components 502 may be triggered by user input or by sensors that detect insertion of the insertion element 500. Sensors could also trigger ejection 504 based on detecting movement or stopping of movement of the plate. For example, when the insertion element 500 stops moving forward, the sensors could trigger ejection.

In some cases, a weight or other pressure element is placed on top of pulp bale 200 to keep it from flexing while press plates 210, 212 press insertion apparatus 214 into pulp bale 200. By crushing upper wrapper 204 and lower wrapper 206 into pulp bale 200, the fold(s) of the wrappers is maintained in place for at least the period required to finish wrapping pulp bale 200.

It should be noted that other variants of the invention are possible. For example, a top part of the pulp bale 200 may be lifted somewhat by a lifting mechanism, allowing for the wrappers to be inserted between sheets 202 of pulp before the top part of the pulp bale 200 is let go and the pressure of the pulp holds the reinserted wrappers in place. One example of a lifting mechanism are forks of a forklift.

With the upper wrapper and lower wrapper fixed, the pulp bale is turned ninety degrees (block 130). This turning process 215 is depicted by FIG. 2 e. In addition, FIG. 2 e depicts crush insertions 216 of upper wrapper 204 and lower wrapper 206 into pulp bale 200 that were created in the previous process (block 125). With the bale turned ninety degrees (block 130), the remaining open ends of pulp bale 200 are covered by folding upper wrapper 204 and lower wrapper 206 over the ends (block 135). This process is depicted in FIG. 2 f. The recently folded ends are then bound by one or more paper straps 218 to hold the folds in place (block 140). The binding process is depicted in FIG. 2 g where straps 218 are wrapped around pulp bale 200 in a single direction. After the binding process, the pulp bale 200 is fully wrapped.

With further regard to the binding process (block 140), the binding process may involve positioning the paper straps 218 at a selected distance from each other and in a single selected direction. The selected distance and direction may depend on the distance between forks 220 of handling equipment and the orientation of the forks 220. For example, the distance between two paper straps 218 may be different from the distance between the forks 220 so that the forks do not rub the paper straps 218. Of note, because paper straps 218 go in a single direction, they are less likely to be interfered with by the forks 220 of handling equipment, where the handling equipment grabs pulp bale 200 such that the forks 220 to not extend perpendicular to straps 218. For example, forks 220 are directed at the bale 200 in a direction substantially parallel to the straps 218. The pulp bale 200 together with wrappers and paper straps may then be placed together in a pulp making vat.

With more specific regard to the paper straps 218, paper straps may be formed in numerous different ways. By way of example, and without limitation, paper straps and methods for creating paper straps are shown and described in U.S. Pat. No. 7,118,684, entitled “Paper Strap”, issued on Oct. 10, 2006 to Edward Dever, et al, sharing a common assignee herewith, and which is incorporated herein by reference for all purposes.

Embodiments of the invention have now been described in detail for purposes of clarity and understanding. However, it will be appreciated that certain changes and modifications may be practiced within the scope of the appended claims. Accordingly, it should be recognized that many other systems, functions, methods, and combinations thereof are possible in accordance with the present invention. Thus, although the invention is described with reference to specific embodiments and figures thereof, the embodiments and figures are merely illustrative, and not limiting of the invention. Rather, the scope of the invention is to be determined solely by the appended claims. 

1. A method for wrapping pulp bale comprising: disposing the pulp bale between an upper wrapper and a lower wrapper; wrapping the pulp bale in the upper wrapper and the lower wrapper; and maintaining at least one of the upper wrapper and the lower wrapper in a wrapped position by crushing the at least one wrapper into the wrapped pulp bale.
 2. The method of claim 1, further comprising binding the wrapped pulp bale with at least one paper strap.
 3. The method of claim 2, wherein binding the wrapped pulp bale comprises orienting the at least one paper strap in a direction substantially parallel to forks of handling equipment.
 4. The method of claim 3, wherein binding the wrapped pulp bale comprises positioning the paper straps at a distance from each other that is different from a distance between the forks of the handling equipment.
 5. The method of claim 2, wherein the at least one paper strap is oriented in a single direction.
 6. The method of claim 1, wherein crushing the at least one wrapper into the wrapped pulp bale comprises applying press plates to opposing sides of the pulp bale.
 7. The method of claim 1, wherein crushing the at least one wrapper into the wrapped pulp bale comprises lifting a portion of the pulp bale to allow for insertion of the at least one wrapper into the pulp bale.
 8. The method of claim 6, wherein crushing the at least one wrapper into the pulp bale further comprises placing a pressure element on top of the pulp bale to prevent flexing of the pulp bale during crushing of the pulp bale.
 9. The method of claim 6, wherein applying press plates to opposing sides of the pulp bale comprises pressing one or more insertion apparatus into the upper wrapper and the lower wrapper.
 10. The method of claim 5, further comprising rotating the pulp bale to orient the at least one paper strap in the single direction.
 11. A system for pulp bale wrapping, the system comprising: at least one press plate operable to press a wrapper into a pulp bale.
 12. The system of claim 11, wherein the at least one press plate comprises a pair of press plates operable to be applied to opposing sides of the pulp bale to crush the wrapper into the pulp bale.
 13. The system of claim 12, wherein the at least one press plate comprises at least one insertion apparatus configured to crush the wrapper into the pulp bale.
 14. The system of claim 11, further comprising at least one paper strap binding the wrapper around the pulp bale in a single direction.
 15. The system of claim 14, wherein the single direction is substantially parallel to forks on handling equipment.
 16. The system of claim 15, wherein the at least one paper strap comprises two paper straps positioned at a distance from each other that is different from the distance between the forks.
 17. The system of claim 13, wherein the at least one press plate comprises a plurality of insertion apparatus, wherein each of the insertion apparatus has a shape.
 18. The system of claim 17, wherein at least two of the insertion apparatus have a different shape.
 19. The system of claim 11, further comprising a lifting mechanism operable to lift at least a portion of the pulp bale while pressing of the wrapper into the pulp bale.
 20. The system of claim 11, further comprising a plurality of wrappers, wherein the plurality of wrappers comprises a lower wrapper disposed beneath the pulp bale and an upper wrapper disposed on top of the pulp bale. 